Stock-Based Compensation And Employee Stock Option Plan (Narrative) (Details) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Excess tax benefit from share-based compensation, financing activities	$ 0	$ 0	$ 0
Compensation expense	146,000	199,000	285,000
Options granted	80,000	175,000	206,000
Unrecognized estimated compensation cost related to non-vested stock options granted	446,000
Recognition period of unrecognized compensation cost	2 years 6 months
Realized value of option exercised	321,200	133,000	321,200
Cash received from exercise of stock options	978,000	248,000
Intrinsic unrealized value of all options outstanding, vested and expected to vest	4,197,000
Percentage of option currently exercisable	59.00%
Expiration period for stock options	10 years
Common Stock authorized for issuance under 2010 Stock Incentive Plan	1,250,000
Weighted average remaining contractual life of all options outstanding, vested, and expected to vest	2 years 5 months 9 days	4 years 8 months 12 days
Weighted average remaining contractual life of the exercisable options outstanding	3 years 1 month 10 days	3 years 7 months 17 days
Terminated Employees [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise period	3 months
Class A [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Forfeiture of shares	64,000
Stock issued	157,600	62,500	95,000
Options exercised	157,600	137,500	136,000
Exercise price per share	$ 6.21	$ 3.98	$ 4.68
Class A [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted		217,890
Stock issued	125,209		155,925
Class A [Member] \| Employee Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted			9,680
Stock issued			9,680
Compensation expense			44,000
Incremental Shares Issued [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Realized value of option exercised		124,000	103,000
Options exercised		75,000	41,000
In the money shares exercise of options, net		53,136	15,822
Exercise price per share		$ 4.01	$ 4.01
Market price per share		$ 5.66	$ 6.53
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options	0 years
Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period of stock options	4 years
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares granted	160,643	125,209	227,570
Restricted stock compensation expense	1,200,000	750,000	994,000
Restricted Stock [Member] \| Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Value of stock granted	1,200,000	750,000	950,000
Shares granted	160,643	125,209	217,890
Share price of stock granted	$ 7.47	$ 5.99	$ 4.36
Restricted sale period	5 years
Restricted shares issued	125,209
Shares issued, price per share	$ 5.99
Fair value of shares issued	$ 750,000

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Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options, Grants In Period, Total Fair Value

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Share Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options, Total Fair Value

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Share-based compensation arrangement by share-based payment award percentage of options exercisable.

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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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Aggregate proceeds received by the entity during the annual period from exercises of stock or unit options and conversion of similar instruments granted under equity-based payment arrangements.

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Unrecognized cost of unvested share-based compensation awards.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of cash inflow from realized tax benefit related to deductible compensation cost reported on the entity's tax return for equity instruments in excess of the compensation cost for those instruments recognized for financial reporting purposes.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Weighted average remaining contractual term for fully vested and expected to vest options that are exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share instruments newly issued under a share-based compensation plan.

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Amount per share or per unit of equity securities issued by non-development stage entity.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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